The series of naturally occurring furanonaphthoquinones is extended by identification of the derivatives 2-(1'-methylethenyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione and 2-(1'-methylethenyl)-7-hydroxynaphtho[2,3-b]furan-4,9-dione. They are accompanied in the stem barks of Newbouldia laevis by the known analogues 5-hydroxy-dehydro-iso-alpha-lapachone, 2-acetyl-5-hydroxynaphtho[2,3-b]furan-4,9-dione and 2-(1'-methylethenyl)naphtho[2,3-b]furan-4,9-dione along with the rare atraric acid and the new 2-(1'-methylethenyl)-6-hydroxy-2,3-dihydrobenzofuran. The structures of these compounds were established from spectroscopic studies.

中文翻译：

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Newbouldia laevis茎皮中的呋喃并萘醌，阿曲酸和苯并呋喃。

通过鉴定衍生物2-（1'-甲基乙烯基）-5-羟基萘[2,3-b]呋喃-4,9-二酮和2-（1'-甲基乙烯基）-7扩展了一系列天然的呋喃萘甲醌类化合物。 -羟基萘并[2,3-b]呋喃-4,9-二酮。它们在Newbouldia laevis的茎皮中伴随着已知的类似物5-羟基-脱氢-异-α-lapachone，2-乙酰基-5-羟基萘[2,3-b]呋喃-4,9-二酮和2- （1'-甲基乙烯基）萘[2,3-b]呋喃-4,9-二酮与稀有的草酸和新的2-（1'-甲基乙烯基）-6-羟基-2,3-二氢苯并呋喃。这些化合物的结构是通过光谱研究确定的。